This invention relates to an apparatus for removing or filtering contaminants from a gaseous emission such as smoke. More particularly, this invention relates to such devices which are preferably disposed in advance of a stack or some similar outlet, whereby certain contaminants are removed before the gaseous emissions escape into the ambient air.
At the present time, particularly in view of the well-known effort to prevent further degradation of the environment, it would be very desirable to provide economical means for removing contaminants, such as particulate matter and other pollutants, from gaseous emissions prior to their escape into the biosphere. Numerous devices have been suggested for this purpose with varying degrees of success. Some of these devices have utilized an array of traps through which gaseous emissions are circulated en route to a stack. As the gaseous emissions pass through these traps, the associated particulate matter adheres thereto, permitting the gaseous emissions to enter the stack substantially free from the contaminating particulate matter. In some prior art embodiments, the gaseous emissions are subjected to a liquid spray in advance of the traps so that, among other things, the particulate matter will adhere to the traps more readily.
Though many of these prior art devices have successfully removed particulate matter and other pollutants from gaseous emissions, some of them are subject to the undesirable effect of particulate buildup. More particularly, as gaseous emissions are continuously circulated, the amount of trapped particulate matter tends to increase. If this particulate matter is not removed, the traps can become coated with layers of particulate material which can clog the traps and interfere with the proper circulation of the gaseous emissions. Moreover, in some prior art embodiments utilizing a liquid spray in advance of the traps, a portion of the spray undesirably passes therethrough and into the stack.